Septic systems are common systems for treating wastewater. Most septic systems comprise an inlet pipe, a septic tank, an outlet pipe, and an absorption component. The septic tank is designed to hold wastewater for a period of time to allow bacteria to break down organic material in the wastewater and to permit heavier solids to settle at the bottom of the tank. These actions reduce the amount of organic material leaving the septic tank compared to what enters. The wastewater leaving the septic tank via the outlet pipe enters the absorption component, where the water passes back to the ground. Any remaining organic material in the wastewater collects in the absorption component.
Over time, the settled solids at the bottom of the septic tank accumulate to the point that they have to be pumped out. At the same time, the level of organic material collecting in the absorption component also accumulates, but there is no efficient way to remove these solids. Eventually, the organic material accumulation in the absorption component becomes so great that the absorption component can no longer pass water from the septic tank to the ground, and the system is considered to be in failure.
Wastewater aeration systems are typically used to remediate a failed septic system or to improve the operating efficiency of a functioning septic system. See U.S. Pat. Nos. 7,264,727; 7,429,320; 7,468,135; 7,708,259; and 7,718,067. The purpose of these systems is to introduce and increase levels of dissolved oxygen in the wastewater and change the dominant life-respiration processes from anaerobic to aerobic. Aerobic bacteria are dramatically more efficient and faster at breaking down organic material in wastewater into simpler solids and gases than anaerobic bacteria. As a result, consumption of organic waste by aerobic bacteria is increased and turbidity and suspended solid levels drop dramatically. These processes can also extend into and benefit the absorption component of the septic system, wherein residual organic matter is broken down and water is passed back to the ground at increased efficiency.
Septic system aeration is most often performed in the septic tank because this is where the bulk of the organic waste breakdown occurs. Almost all septic tank aeration systems introduce air into the wastewater by a positive displacement air pump. The air pump is connected to one or more lengths of flexible or rigid tubing that are placed in the wastewater and are connected to diffusing devices that break up the air into small bubbles, greatly improving the transfer of oxygen from the air to the wastewater.
While the aeration process described above dramatically improves wastewater processing compared to an anaerobic environment, one significant problem is that the flow of air bubbles to the surface of the water creates turbulence in the septic tank. The turbulence has two negative consequences: It disrupts the solid settling process and disturbs solids that have settled. As a result, even though turbidity and suspended solid levels drop dramatically in the wastewater leaving the septic tank, they are not as low as they could be because of the turbulence introduced by the aeration process. If turbulence were to be reduced in the aeration process, even cleaner wastewater would leave the septic tank, further reducing the amount of solids entering the absorption component and improving the operational efficiency of the entire system. There is a need for an aeration system that efficiently aerates liquid and minimizes turbulence.